Research will continue into alcoholism as a behavioral disorder. Participants are volunteer human alcoholics. The project is directed toward experimental assessment of environmental, behavioral and pharmacological procedures which can be effective in modifying alcoholics' drinking behavior. This involves identifying, establishing control over, and manipulating relevant controlling variables so as to modify alcohol self-administration. This task is pursued concurrently in two areas. First, the operant psychology methods of the experimental analysis of behavior are utilized in basic research on modifying alcoholics' drinking within a laboratory setting. Second, the methods of behavior modification or contingency management are utilized in developing and evaluating clinical extensions into experimental treatment programs for sustaining sobriety within alcoholics' natural environment. The alternative treatment goals of abstinence and moderation will both receive attention. The studies should contribute to an empirical base for the development and implementation of improved treatment and control procedures for alcoholism.